Convert image to byte array

I would like some code or worst case a utility that can take an image, .jpeg, .bmp, .... and convert it to it's hexidecimal representation in an array. Code wise just straight c. NO C##, VB, etc.

Thank You
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sarabandeConnect With a Mentor Commented:
you may use the following code:

int binfile2hexstring1(const char * inputfile, char hexbuf[], int sizbuf)
     char hexdigits[] = "0123456789ABCDEF";
     struct stat fs = { 0 }; 
     FILE * file;
     char * buf;
     int nread;
     char ac[3];
     int n;
     char * p, * q;

     if (stat(inputfile, &fs) != 0 || fs.st_size == 0)
          return errno;   // file does not exist or is empty
      if (sizbuf < 2*fs.st_size)
           return -1;  // hex buffer to small
      file = fopen(inputfile, "r");
      buf =  (char*)calloc(fs.st_size);
      if (file == NULL ||buf == NULL)
            return errno;
     if ((nread = fread(&buf[0], 1, fs.st_size, file)) < (int)fs.st_size)
          return errno;  // invalid read
     p = &hexbuf[0];
     q = &buf[0];
     for (n = 0; n < (int)fs.st_size; ++n)    
       *p++ = hexdigits[((*q)&0xf0)>>4];  // convert high half-byte
       *p++ = hexdigits[((*q)&0x0f)];         // convert low half-byte
     return 0;

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the code is pure c "derived" from an older question where we not only discussed conversion to hex but also differences in speed using c or c++ solutions.
see for more.

If C++ is an option and it is a Windows environment then have a look at CImage class. Requires MFC.

Otherwise, have a look at GOCR library. The library itself is a OCR library. You do not have to use it, however there are two files there pnm.h and pnm.c that can handle many of known image files. have a look at readpnm() function there. I have used this library for OCR purposes in one of my projects. You can just use the pnm files, I guess, check its license.
atomicgs12Author Commented:
Thanks but only C, I tried to cover all the languages not to use guess I have to make my list longer.
No C#, No VB, No C++, No Python, No Pascal, No Fortron, No HTML, No Silverlight, No...
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atomicgs12Author Commented:
Looking at GOCR file pnm.c I don't see a ' readpnm() ' I do see a 'readpgm()' which I'm assuming your referring to. Even in that function I don't see an explanation as to to the input variables. I'm assuming 'char *name' is the name of the picture file, put I don't know what 'pix *p' and 'int vvv' are referring to.
William SherifCommented:
I would use SDL

Load the image using IMG_Load (or if you're using a png, use the SDL_Image 2.0 library).

After you load the image, you can inspect the contents of the surface using the pixels member of the SDL_Surface object (see

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atomicgs12Author Commented:
Need to try the suggested solution before selecting a correct answer(s).
Thank you all
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